Reading:: New Field of Entomotoxicology!

Entomotoxicology: A Review
By Murthy, Dr. C.R. Vasudeva & Mohanty, Manisa.


  This article was not included in my original plan at the start of my project, but it caught my attention and I think it is extremely interesting.

Forensic entomology is the study of the effects that insects have on a decomposing body and the information that these effects can offer to a forensic investigation. This information includes time of death, movement of the body, antemortem injuries, and drugs and toxins present at time of death. It is a fairly new field and there has not yet been extensive research on its reliability for obtaining forensically useable data. Scientists have begun to prove that it is possible to analyze the insects on a decaying body determine the types and amount of drugs that were present or absent in a decadent’s body at the time of death. This is called entomotoxicology. This is helpful as an alternate drug testing method because many drug-related deaths are left undiscovered for a long enough period of time for severe decaying and/or skeletonization to occur, making it impossible to use tissue or blood samples for conventional drug tests. This article reviews the methods and theories of entomotoxicology.

In order to prepare the insects for testing for inorganic substances, they must be cleaned, dried and crushed, then put into storage -20 to 4 degrees Celsius until the actual analysis begins. For testing of organic substances the insects are also cleaned, dried, and cut up into fine pieces, then they are mixed with an interna standard solution. The insects are homogenized in a .9% saline solution then centrifuged. The acids break down the larvae’s exoskeleton, which releases any toxins that are present. Then the acid solution is removed from the specimens and the organic substances can be analyzed.

Methods for analysis include mass spectrometry, high performance layer chromatography, thin layer chromatography, radio immune assay, and gas chromatography.

Different drugs have differing effects of the decomposition rates of carrion insects. Heroine speeds up the growth of larva and slows down the developmental pupal stage, while cocaine and methamphetamine simple speed up the rate of fly development. A lethal dose of cocaine causes larvae to develop faster between 36 and 72 hours after they hatch. In a test-control experiment, it was proven that maggots feeding on flesh rich with methamphetamine fed faster and grew larger than the maggots feeding on flesh without any drugs present.

Although carrion insects are a great source for drug detection, more research needs to be done in order to actually quantify the drug concentrations found in the anthropods. Not only can insects provide valuable forensic information regarding the time since death, they can be helpful in determining if intoxication was an implication of the decadent’s death.

Resource:

Murthy, Dr. C.R. Vasudeva & Mohanty, Manisa (2010). Entomotoxicology: A
             Review. Journal of Indian Academic Forensic Medicine, 32(1), 82-84.